Kiln



-sepfn 11, 1928.

H. M. ROBERTSON KILN 2 .sneakssheet 2 Filed Jan. 28, 1928 1 ,IIIIIII'IIII Patented Sept. V1l, 1928.

UNITED STATES PATENT oFmcE.N

HARRY M. ROBERTSON, OF CLEVELAD, OHIO.

XILN.

Application inea January 2s, 192s.` serial No; 250,294.`

This invention relates to tunnel kilns in which `material is passed through a zone of heat capable of calcining, firing or otherwise treating material or articles in large quantities.

One object of the invention is to provide a novel kiln structure in which the residue, such as dust, ashes and/orcinders, due to combustion of pulverized coal and like fuel or other form of fuel instead of passing into the area occupied by the material treated, will be collected or caused to settle out of the path of the fire and subsequently to be re* moved at the convenience of the operator. This removal may be accomplished without interrupting or in any Way interfering with the continuous operation of the kiln.

Another object of .my invention is in providin facilities for access to the combustion chamer for whatever purpose may be deisired. Among such purposes may be noted .the inspection of the operation yof the tiring;

Y that is, Whether the `combustion is taking place in the manner intended. Also it may be desired under some circumstances to supply fresh air to the combustion chambers inde-` pendently of the fuel ports. Access to these combustion spaces at a pointbeneath the zone of combustion is also important in the roper care of the spaces and the removal o dust, ashes and the like.

Other objects of my invention will be evi dent from` the following description taken in connection with the accompanying drawings illustrating my preferred embodiment of the invention. On these drawings?- Fig. 1 is a horizontal longitudinal section,

on the linel-l of Fig. 2, Vof a portion of a p kiln embodying my invention; p Fig. 2 is a vertical longitudinal section on the line 2-2 of Fig. 1;l y

Fig. 3 is a vertical cross section on the line 3-3 of Fig. 1; y

Fig. 4 is averticalcross section on the line H of Fig. l; and

Fig. 5 is a vertical cross section on the line i 5-5 of Fig. l. Y

As illustrated in the drawings I have shown a portion of a tunnel kiln'of generally conventional type so far as itsmain structure is concerned and in which my improvements have been embodied, such kiln in the presenty embodiment comprising a heating zone A, a preheating zone B and a cooling zone O, only portions of the zones B and O being shown. The base or foundation 6 maybe of any suitcontinuously able vmaterial, but as illustrated itis preferably of monolithic concrete. Longitudinally i B, A and O through the center of the Zones are mounted the rails 7 of a track `along which, in successive order, trucks .carrying the material to be treated can be conveyed. The foundation Gsupports on each side a series of vertical metal I-beams 8, connected at their upper ends by transverse tie rods 9.

By this means the outer Walls 10, of the kkiln are held in properposition. These walls 10 may be of masonry, brick orl concrete.

An inner Wall 1111 extends parallel to` each of the outer walls 10-10 and spaced from thelatter. Suitable heat yinsulating filling 12-12 occupies the spaces between the inner and outer walls. The inner Walls are made of material similar to that of the outer walls.l Bridging the'space between the top of the inner walls 1111 and the corresponding portions of the outer walls a suitable plate or other cap v13 is provided.V `Inwaidly of the plates 13 are pediments 1414 which support in turn the ends `of the roof arch 15. The

entire top of the kiln within the outerwalls l0- 10 is covered with a suitable heat insulating iilling 16.

Ledges 17-17 rise vertically from the base, Within the heating Zone A and extend from` end to end thereof. Theseledges 17 are also formed of masonry or other suitable mate rial andspaced from the inner walls 11-11, to support vertical partitions of open brick or checke-r-work 18` through 'which the heat.

passes. Opposite each Wall of brickvvork 18 and in spacedjrelation thereto is a fireback 19 mounted against the Walls 11-11 to protect the latter from the high temperatures obtained. Across the top extending from the` brickwork 18 to theadjacent iireback 19 is a top partition 20 having vertical battles 21 suitextend inwardly close to theA passageway` through the kiln leaving only enough vclearance for the customary trucks. As illustrated in Fig. 3,'each ba is defined byspaced transverse Walls 10', an inner wall 11', and by a roof slab 23, the Wall 11' being in the same plane with the checkerwork 18 so that the hay will extend inwardly beyond the plane. of the adjacent combustion chamber 24 and a settling or collecting chamber 26.

Referring again to Figs. 1 and 5 it Willbe seen that at either side of the space for the material (a) a combustion chamber 24 is formed by the fireback 19, checkerwork 1S and slab 20, abovethe level of series of fuel ports or fire boxes; and (b) thel spacing of the ledge 17'fromthe fi'reback 19 and Walll 11 forms the settling or collecting chamber 26 extending from end-to end of the heating zone'a'ndin communication throughout its length with the adjacent combustion chamber 24- and` each of the fuel ports or lire boxes 25, so' that the products of'combustion flow from the fuel ports through the upper portion of the settling chamber to the combustion chamber. As the settling chamber is directlybelow the combustion chamber, all the residue incident to combustion will fallthereinto, instead of passing outwardly through the checkerworki18. The combustion chambers 24. extend on each side ofthe line of travel ofthe material for'the full distance of the heating zone and have a bay 22 at each end thereof.

As shown byway of example this combustion chamber is served by four fuel ports '25. These `ports may beadapted for the burnino of pulverized fuel but other fuel may r be usedH as desired.

At the ends of the settling chambers, the inner side Walls 10 of the bays are pierced ito provide clean-out ports or passageways 27 It will be noted that these ports are on the level of the settling chamber 26 and beneath the combustionV chamber 24. These ports are shown as inwardly flaring (Fig. 1), and by preference, the inner surfaces of the ledges 17 are inclined outwardly so that the bottoms o; they chambers 26 are in line with the ports 2 It will be evident that the inlet ports 25 will admit streams ofgaseous or pulverized fuel mixtures in sufficient quantity to establish an area of intense'heat Within the combustion chambers 24, from which the hot gases pass through the brickwork`18 into thearea occupied by the trucks carried on the rails 7;'7." Suitable means (not illustrated) are provided forventing the products of combustion or forl causing them to flow toward one end of the kiln. However, it is not feasible to allow any solid particles, dust, ashes or other residuethat may occur as products of combustion to travel in this course and the settling chambers 26 beneath the chambers 24; serve'the purpose of entraining such materials and holding the same as a deposit.

By providing at each end of each settling chamber 26, a suitable-clean-out port 27 it is a matter of ease to remove these deposits therefrom as fast as they accumulate. This may be done in any of a number of ways as will occur to those skilled in this industry, for example a blast of steam, air or the like from a nozzle may be directed in the port 27 at one end of either chamber 26 and the accumulated materials thus driven out through the opposite clean-out port 27. As there isbut one collecting chamber 26 for each series of lire boxes and this chamber is co-extensive with the adjacent combustion chamber and open at its opposite ends, all of the accumulated residue may be cleaned out at onefoperation, at will. Again the nozzle of a vacuum hose line may he passed in a port 27 andthe material drawn out of the chamber 26 directly. In either event the operation of the kiln is not interfered With.

Numerous changes in pro iortion and minor details may be made Wit in the scope of this invention and without departing from the sense of the claims.

What I claim is: v y

1. In a tunnel kiln, a `longitudinally eX- tending combustion chamber, a fuel port, a settling chamber connecting said fuel port with the combustion chamber, and a clean-out port at one end of said settling chamber.

2. In a tunnel'kiln, a combustion chambery extending throughout a portion ofthe kiln, a longitudinal series of fuel ports, a settling chamber common to said ports and connecting them with said combustion chamber, and

a clean-out port at one end of said settling chamber.

3. In a tunnel kiln, a combustion chamber extending throughout `a portion of thekiln, a longitudinal series of fuelports, a settling chamber common to said ports and connectin'g them with said combustion chamber, and a clean-out port at each end of said settling chamber.

4. In a tunnel kiln, a combustion chamber, a fuel port beneath said combustion chamber, a settling chamber connecting the fuelport with the combustion "chamber, and a cleanout port at one end of said settling chamber.

5. In a` tunnel kilnfa combustion chamber, a longitudinal series of fuel ports, a `settling chamber common to said portsl andy connecting them with said combustion chamber, and a clean-out port at one end of said settling chamber beneath the level of the combustion chamber.

6. In a tunnel kiln, a combustion chamber longitudinally along one side of said kiln, a settling chamber beneath and coextensive with said combustion chamber, a series of fuel ports leading into said settling charnber,.and a clean-out port openinginto each end of the settling chamber.

7. 'Int a tunnel kiln, a combustion chamber longitudinally along one side of said kiln, a

settling chamber beneath and coextensive with said combustion chamber, a series of fuel ports leading into said settling chamber, and a clean-out port openingr into each end of the settling chamberv on the level of the fuel ports. Y Y

8. In a tunnel kiln having side walls forming a heating zone, bays in one of said side walls at the ends of said zone, a combustion chamber within said side wall extending between said bays, and a clean-out port opening inwardly from eachbay into the area beneath said combustion chamber.

9. In a tunnel kiln having side walls forming a heating zone, bays in one of said side walls at the ends of said zone, a combustion chamber within said side wall extending between said bays, a settling chamber beneath said combustion chamber, and a clean-out port opening inwardly from each bay into the settling chamber. Y

10. In a tunnel kiln having sidewalls forming a heating zone, re-entrant walls at the ends thereof forming bays at each end of said zone, a longitudinal series of fuel ports in each side wall, a common combustion chamber for each series of ports extending between said bays,v settling chambers connecting the fuel ports `withthe combustionV chambers and a clean-out portopening in# wardly from each bay into f the settling chambers at the level of the fuel ports.

In testimony whereof I aiix my signature.

HARRY M. ROBERTSON. 

